After playing for so long, with a city that has past the 400 years, I’m wondering why traders always buy the same (rotating) stuff, I have warehouses completely full of items that I cannot get rid of simply because I don’t consume it enough and traders never ever asks for them.
Any item present in the game should be eventually asked for trade in by traders, sure some more than others, some just occasionally, but there should be a chance to sell them.
Better control over Trade, as in being able to request certain items be offered by the Traders, perhaps for extra Gold, has been requested several times, and doubtless they are looking at some kind of enhancement to the system. Especially with the increase in potential populations over 1000, some more reliable way of getting extra resources will be required to make many maps playable at high population levels.
In this case, adding all potential resources available to the town to the trade system should be part of that, perhaps with a Trader who only comes by every few years but is willing to buy or trade the ‘rare’ items like Paper, Wax, etc.
Not being part of the Development Team, I can only speculate.
But I have noticed that many mechanics in the game are a fine balance, like Gold Income versus cost of Towers and Barracks and other key parts of defenses, or Food versus Housing versus Immigration numbers, so I suspect that the peculiarities in the trading system are part of a balance in requirements versus ease of acquisition: if everything was readily available through the Trading Post, every town would consist of a Trading Post, Town Center, and Housing/Markets - no industry or agriculture or barns required, just Trade.
All of the balancing acts have to be constantly examined, of course, as they add new things to the game (like Paper and Books) or change the maximum population. People have already noted that once the population goes over 1000, Immigration and Births/population increase numbers change for the worse, and availability of resources on some maps (Clay on Alpine, Sand on small Lowland Lakes, for instance) is going to probably be very limited for populations much over 1000.
I can understand the early game and forcing the use of the trading post as an outlet to acquire items that are needed (for example needing heavy tools). Perhaps a solution would be to make more items available to be sold/purchased at T3 and above.
Given that they’ve already hinted for some time that there is a 5th Tier of housing coming, that means (probably) some new requirements for that Tier, and 1 - 2 new Luxuries for them. That means some more tweaks to Production or Trading systems or both, with possibly new uses for some resources we already have or get from the new animals proposed.
Then, of course, all that will have to be balanced along with (probably) rebalancing the existing Tiers so the game doesn’t have a bottleneck in the development of the towns, and I would be very, very surprised if that balancing did not include another hard look at the Traders, what they buy, what they sell, and how trading works with or instead of production.
I don’t envy them trying to make it all work smoothly. As much as we complain, the fact is the game works remarkably well for a pre-release version with as many different things going on in it: production, transportation and storage of food, luxuries, necessities; trade, defense, spirituality, health, maintenance, etc.
I can’t argue with your assessment in the least - they devs are doing a great job with balance. Have an engaged community providing input (idea, feedback, etc) only shapes the game for the better. At over 500 hours in thus far I’m still learning new tricks!